Axle assembly



Dec. 16, 1941. B, L, MILL 2,266,061

AXLE AS S EMBLY Filed May 6, 1939 2 Sheets-Sheet 1 INVENTOR imam/m, 0/44 s.

ATTORNEY 7 B. L.- ivuLLs 2,266,061

AXLE ASSEMBLY Filed May 6, 1959 2 Sheets-Sheet 2 INVENTOR fiw/Prm 4. 0,4115.

, ZWEM v ATTORNEY Patented Dec. 16, 1941 AXLE ssssivm x Burton L. Mills, Buchanan, Mich assignor to Clark Equipment Company, Buchanan, Mich,

a corporation of Michigan Application May 6,1939, Serial No. 272,085

15 Claims.

This invention is directed to axle assemblies, and more particularly is directed to an axle assembly for dead axles, such as used in trailers,

semi-trailers, and the like.

It has been found that there is considerable scufiing of tires on 'dual wheel axle assemblies on large trailers and the like caused by variations in the turning radii of the individual wheels which results in the inner wheel of theturning are rotating slower than the outer wheel.

As the two wheelsare locked against rotation,

there is a consequent scuffing of the tires which produces undue wear, as well as increasing the force required in turning,

The present invention contemplates broadly the provision of two independent wheel bodies mounted on the end of the axle for relative ro-- tation so that a diilerential movement therebetween is provided during turning, or in cases where the tread diameter of the tires varies so that one wheel rolls on a smaller circle than the other. The inboard wheel of the, assembly is .provided with a brake drum rigidly secured thereto in order to transmit braking torque to this wheel. Since the two wheels are independ ently rotatable, some means must be provided for applying a similar braking torque to the outboard wheel in order to prevent unequal wear of the wheels caused by the braking.

In the present invention this is accomplished by using a stub axle arm of tubular form through which extends a shaft having a flanged end secured to the hub of the outboard wheel. At the opposite end this shaft is journalled in the inner end of the tubular axle, and carries a brake drum which is rotatable with the outboard wheel. A suitable spring pad casting is pressed over the tubular arm between the inboard wheel and the inner end of the shaft, and has flanges at its opposite ends which carry backing plates coopcrating with the respective brake drums on opposite sides-of the spring journal. These backing plates carry the braking mechanism engageable with the respective drums for' applying braking force to both of the wheels simultaneously.

In order to provide arigid axle structure the spring pad casting is provided with one or more normally extending projections and the two stub axle arms are spaced apart by means of structural members secured to the projecting ends of these extensions. These structural members may comprisechannels, tubes, or the like, and

form a rigid connection between the two axle arms between the spring pads. If desired, op:-

positely extending extensions can be provided on the arms so that 'two such structural members may extend transversely beneath the chassis of the trailer in longitudinally spaced relation and 5 outside of the peripheral limits of the inner brake drum.

Another feature of the present invention resides in an assembly in which the Wheel shafts at opposite sides of the vehicle are so connected as to provide a knee action suspension.

' It is therefore a primary object of the. present invention to provide an axle assembly in which the dual wheels are independently rotatable, but

may be simultaneously braked by means of individual brake drums connected to each of the wheels.

A still further object of the. present invention is to provide a compensating Wheel assembly in which the inboard wheel body has its brake drum disposed laterally outwardly of the brake drum for the outboard body with the two brake drums beingseparated by the spring pad portion of the axle arm.

Other objects and advantages of the present invention will appear more fully from the following detailed description, which, taken in conjunction with the accompanying drawings, will disclose to those skilled in the art the particular construction and operation of a preferred form of the present invention.

In the drawings:

Figure 1 is a vertical quarter sectional'view of an axle assembly embodying the present invention; and

Figures 2 to 5 are somewhat diagrammatic plan views illustrating various forms of axle assemblies embodying the invention shown in Figure 1.

Referring now in detail to Figure 1, a suitable 40 axle housing arm is indicated at 5 and comprises a tubular member having an internal bearing portion 6 at its inner end, and having an outer end of reduced section which has bearing seats formed on its outer surface to receive a series of bearings indicated generally at l, 8 and 9.

Two .wheel bodies l0 and i2 are provided which may be of any desired form, and in the present disclosure areillustrated as being of. the cast spoke type having radially outwardly extending hollow spokes provided with-means for mounting the respective tire rims l3 and I4 thereon. The outboard wheel i2 is of smaller diameter than the inboard wheel so as to allow the rim I3 to be passed thereover into position on the beveled seatl5 formed at the spoke ends of the '25 Of the shaft 21 inboard wheel IO- whereby the gutter edge of the rim l3 may be clamped on this seat by means' rim l4 engages to be clamped inposition by the 5 lugs l8 engaging the gutter edge thereof.

Suitable sealing means are provided between the wheels to preventthe escape of lubricant therepast. This sealing means, indicated at i9, is disposed in axially facing annular recesses formed in the adiacenthubs of thewheels radially outwardly of the bearings 8, and in addition, a suitable closure ring is provided which is snapped over the adjacent peripheral portions of the hubs. This allows the bearings to'be lubricated sufiiciently and yet prevents the discharge of any of such lubricant outwardly between the wheels without preventing any relative rotation between the wheels caused by turning or the like. Similar-sealing means is carried on the housing arm 5 axially inwardly of the bearings 1 to seal the bearing chamber against escape of lubricant axially inwardly between the housing arm and the hub of the wheel spider l0.

' The inboard wheel be clamped between the head flange and these pilots to close the brake drum radially inwardly of the bolts 23 about the hub of the wheel body [0.

The outboard wheel spider 12 has its hub portion on the outer face thereof suitably tapped to receive the bolts 25 which thereto, this shaft extending through the arm 5 and being journalled at its opposite end on the ball bearings 28 carried in the internal, bearing surface 6 of the arm 5. Be-

yond the bearing support 28 the shaft is provided with a tapered end on which is keyed a brake drum 29 secured to the shaft by means of the lock nut 30. It will be noted that the axle arm 5 terminates at the bearing surface 6, and conse-' H! has suitable pilots formed on the inboard side of each of the spokes of'a brake drum 22 may secure the flange end quently the brake drum 29 is free to rotate inwardly of the inner end of the arm 5.

Pressed over the arm 5 and suitably secured thereto by means of welding or the like is a sleeve member 32 which may be in the form of a casting having radially directed flanges 33 and 34 at its opposite ends and having an intermediate spring pad portion 35 on which is mounted the leaf spring assembly 36 secured thereto by means of the U-bolts 31,and the nuts 38. This spring at its opposite ends is shackled to the trailer body, and thereby resiliently supports the trailer body upon the axle arm 5.

Extending rearwardly normal to the axis of the sleeve 32 is an integral projection. 3!! which terminates in a mounting portion 4!) to which is secured the transversely extending channel member 42 forming a structural connection betweentopposite stub axle arms 5. The entire axle: assembly therefore comprises the two stub axle arms 5 connected by a laterally offset structural member 42 which is spaced away from the axis of the arms 5 a sufli- V cient distance to clear the periphery of the brake drums 29 carried at the inner ends of the arms5.

The braking torque is therefore imposed upon the wheels by means of the brake drums 22 and 29 at each side thereof, and braking reactions between the two stub axle arms are taken care of by the transverse connecting member".

applying simultaneous braking action to each of the wheels "I and i2. Thus, while the wheels II and I2 are independently rotatable, they are also simultaneously independently braked by means of the braking mechanisms 45 which can be connected to a common actuating source, such as a pressure cylinder, a hydraulic braking system, or a mechanical linkage.

In Figures 2 to 5, inclusive, I have disclosed various connections'between the axle assemblies on opposite sides of the vehicle for absorbing the braking reaction and holding the stub axle-arms in proper position. The form shown in Figure 2 has already been described, while the form shown in Figure 3 is a variation thereof in which the castings 32' are provided with oppositely extending projections 39' to which are connected the cross members 42 and 52, thus forming a box between the axle arms which is very rigid and is easily able to absorb the braking torque. In Figure 4 a still further modification is provided in which the'sleeves 53 corresponding to the sleeves 32 and 32' are provided with integral projections 54 terminating in collar portions adapted to receive the cross tube 55 which is welded or otherwise non-rotatably secured therein. This is similar to the construction shown in Figure 2, but

36 shown inF-igure 1, that each comer of the structural box formed between the stub axle arms 5, suitable spring pots such as indicated at may be provided adapted to receive vertically extending coil springs which are suitably anchored at their upper ends to the trailer frame so that quadrilateral coil spring suspension is provided for the vehicle body in place of the elastic leaf spring suspension. This may be desired in connection with certain types of bodies and load requirements, and the present invention adapts itself well to such a spring suspension. In Figures 2', 4 and 5, conventional spring pads 35 are provided, as indicated.

It is therefore apparent that I have provided a novel type of axle assembly for dead axles using compensating independently rotatable wheels which can be simultaneously braked by means of separate braking mechanisms.

I am aware that various changes may be made in certain of the details described and illustrated herein, and I therefore do not intend to be limited except as defined by the scope and spirit of the appended claims.

I claim:

1. A compensating wheel assembly comprising a tubular axle spindle, a pair of wheels independently joumalled thereon, a brake drum secured to drum secured to the joumalled end of said shaft. v

- on opposite sides thereoi supporting 2. In combination, a tubular. axle spindle, a pair of wheels independently journalled on said inboard iacing brake drum on the the outboard wheel and extending through. said spindle, and a brake druin on the inner end. of said shaft and facing said first drum.

. 3. The combination of claim 2' further characterized in a spring pad mounting on said spindle and a brake drum secured to the inner end of said spindle axially inwardly of said tubular shaft.

5. In. combination, an axle assembly comprising two tubular spindles arranged in longitudinally spaced alinement, sleeves enclosing the adspring pad mounted on s backing wheel,

of said sleeve portion adapted to form 9. The combination of claim 5 further acterized in that each sleeve has oppositely extending projections with parallel members interconnecting the corresponding ends of the projections, and spring seating means at the end or each projection.

10. In combination, a tubular axle arm, a pair of. wheels independently journalled thereon, a aid arm at one side of a brake 7 sides oi said pad, and means for nonsaid wheels, on. opposite rotatably connecting the remote drum to the wheel disposed farthest from said pad.

11. A spring pad casting for ashort hibular axle spindle including a sleeve portion adapted to receive said spindle and having a spring pad inter-I mediate its ends, a short'radial flange at each brm . backing plate supports, and an integral radial jacent end portions of said spindles and having radial projections, a rigid member interconnecting said projections to connect said spindles together against relative movement, a pair of wheels independently joumalled on the remote ends of each of said spindles, and separate braking disposed in axially spaced relation on opposite sides of said projections, braking means including backing plates secured to opposite ends of each sleeve.

6. In combination, an axle assembly comprising two tubular spindles arranged in longitudinally spaced alinement, sleeves enclosing the adjacent end portions of said shaits and having lateral projections, a rigid member interconnecting said projections to connect said spindles together against relative movement, a pair of wheels .independently journalled on the remote ends or each of said spindles, and separate braking means tor each wheel disposed in axially spaced relation on opposite sides oi! said projections, said sleeves each having spring pad portions intermediate the ends thereof for resiliently supporting a vehicle body thereon.

'7. The combination or claim 5 wherein said projections extend normal to saidspindles and a tube secured at said separate means projection adjacent the spring pad, portion or a length greater than the radius or the backing plates. 1

12. In combination, an axle housing having a spring pad thereon, a brake drum on each side 0! said pad rotatable relative to said housing, a pair of wheels independently journalled on said housing on one side connecting one brake drum to one wheel. and non-rotatably connecting the other brakedrum to the other wheel.

13. In combination, a tubular housing, a pair of end of the spindle, means extending through said spindle and secured at one end to said wheel, and

- secured to the opposite end or each nesting members secured between the corresponding ends of the projections to form a substantially box-like structure.

a brake drum secured to the opposite end thereof adjacent said plate.

15. In combination, spaced tubular ed on the outer a pair of longitudinally end of each spindle, a brake plate mounted on the inner end of each spindle, ashait extending through each spindle and connected at one end to the associated wheel, a brake drum shalt adiacent said plate, normally extending projections on each spindle intermediate said} wheel and brake, andan interconnecting member secured to the-ends of said projections.

BURTON L. urns.

drum for each wheel I of said pad, means non-rotatahly' side by side relation on oneof said housing ior independent rotation, a

a tubular axle spindle, a

mounted at the opposite spindles, a wheel rotatably mount- 

